FCMTopicSubscriber

java.lang.Object
- com.amazon.A3L.messaging.FCM.topicsubscription.FCMTopicSubscriber

```
public class FCMTopicSubscriber
extends java.lang.Object
```
Handles the topic subscription and unsubscription operations for Firebase Messaging.

Constructor Summary

Constructors
Constructor Description

FCMTopicSubscriber()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`com.google.android.gms.tasks.Task<java.lang.Void>`	`subscribeToTopic(java.lang.String topic)`	Invokes the FCM's subscribeToTopic method which subscribes the deviceToken to the given topic.
`com.google.android.gms.tasks.Task<java.lang.Void>`	`unsubscribeFromTopic(java.lang.String topic)`	Invokes the FCM's unsubscribeFromTopic method which unsubscribes the deviceToken from the given topic.

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - FCMTopicSubscriber
```
public FCMTopicSubscriber()
```
- Method Detail
  - subscribeToTopic
```
public com.google.android.gms.tasks.Task<java.lang.Void> subscribeToTopic(@NonNull
                                                                          java.lang.String topic)
```
    Invokes the FCM's subscribeToTopic method which subscribes the deviceToken to the given topic.
    
    Parameters:
    
    topic - : Topic to which the app instance is to be subscribed.
    
    Returns:
    
    Task which can be used by completion listener to determine whether the subscription completed.
  - unsubscribeFromTopic
```
public com.google.android.gms.tasks.Task<java.lang.Void> unsubscribeFromTopic(@NonNull
                                                                              java.lang.String topic)
```
    Invokes the FCM's unsubscribeFromTopic method which unsubscribes the deviceToken from the given topic.
    
    Parameters:
    
    topic - : Topic from which the app instance is to be unsubscribed.
    
    Returns:
    
    Task which can be used by completion listener to determine whether the subscription completed.